The dimensions of hoisting devices and cranes are generally chosen such that the forces imposed on the various components are within a safe range, i.e., such that failure is unlikely.
In this respect, however, there is a distinction between static and dynamic forces. Static forces are forces that occur when the load is either suspended on the load receptacle means in a motionless fashion or is moving at a constant speed. Dynamic forces, on the other hand, are imposed when the speed at which the load is moved by the load receptacle means changes more or less abruptly, i.e., when the load is accelerated or decelerated. The greatest changes in speed occur when the load is lifted off of a support or, even more critically, when the movement of the load needs to be abruptly stopped due to an emergency situation. In the latter case, the load must be quickly stopped from high speed, e.g., maximum speed. This type of deceleration can impose very high peak forces.